Mentions:
We electroporated NSD3Δ1707 or pMES into one- to four-somite cranial neural folds (HH stages 7–8; Figure 7A). After incubating electroporated embryos to migratory stages, we visualized migratory neural crest cells using Sox10 in situ hybridization. Delays in neural crest migration were apparent in 100% of NSD3Δ1707-electroporated embryos (Figure 7, C and D). Of these, 75% exhibited moderate to severe defects, compared with mild disruptions in only 33.3% of pMES electroporated embryos (Figure 7, B and D, p = 3.8 × 10−4). NSD3Δ1707-expressing neural crest cells emigrated from the neural tube but appeared to halt en route (Figure 7C), suggesting that dominant-negative activity commenced in actively migrating cells. This effect was sometimes apparent throughout the population, so that the extent of migration was reduced compared with the untargeted side of the embryo (Figure 7C, white arrowhead), as seen after gastrula-stage MO electroporation (Figure 6, B, E, and F). Alternatively, groups of cells trailed the rest of the normally migrating population or did not migrate away from the midline (Figure 7C, white arrow). These data indicate that methylation by NSD3 or a related methyltransferase directly regulates neural crest migration.

Mentions:
We electroporated NSD3Δ1707 or pMES into one- to four-somite cranial neural folds (HH stages 7–8; Figure 7A). After incubating electroporated embryos to migratory stages, we visualized migratory neural crest cells using Sox10 in situ hybridization. Delays in neural crest migration were apparent in 100% of NSD3Δ1707-electroporated embryos (Figure 7, C and D). Of these, 75% exhibited moderate to severe defects, compared with mild disruptions in only 33.3% of pMES electroporated embryos (Figure 7, B and D, p = 3.8 × 10−4). NSD3Δ1707-expressing neural crest cells emigrated from the neural tube but appeared to halt en route (Figure 7C), suggesting that dominant-negative activity commenced in actively migrating cells. This effect was sometimes apparent throughout the population, so that the extent of migration was reduced compared with the untargeted side of the embryo (Figure 7C, white arrowhead), as seen after gastrula-stage MO electroporation (Figure 6, B, E, and F). Alternatively, groups of cells trailed the rest of the normally migrating population or did not migrate away from the midline (Figure 7C, white arrow). These data indicate that methylation by NSD3 or a related methyltransferase directly regulates neural crest migration.